If the Crocodile Hunter can be killed by a stingray, then that means anyone (who dives into the ocean that is) can be its victim. There are 5000 reported stingray attacks in the US alone, though the fatality rate is very low.

A wikihow tells how to treat a minor stingray attack. You should remember this though;

Vinegar, urine, orange juice, ki-ora or any other liquid besides almost-scalding hot water will NOT be effective against stingray venom. (Acids may, however, ease jellyfish stings.)